Enhydra – Sea otter

They can sleep in the sea by lying on their backs and floating on the surface of the water

The sea otter is the heaviest weasel but the lightest marine mammal. They have a thick coat, undercoat, and a layer of longer guard hairs. This enables them to trap air and act as an insulating layer to keep them warm. After eating, they clean their coat with teeth and paws to keep it waterproof and insulated against the cold.

They were once hunted excessively, reducing the population number from 300,000 animals in the 1700s to only 2,000 animals in the early 20th century, which makes them on the brink of extinction. Currently, they are protected by laws but are still listed as Endangered.